A flexible display is a deformable and flexible display unit, made of a soft material. The flexible display can be as thin as paper, and even if the power is cut off, the content in the display will not disappear, so the flexible display is also referred to as “electronic paper”. Because of the characteristics of being extremely light and thin and having low power consumption and being deformable, the flexible display is already widely used in portable electronic devices. The bending performance of the flexible screen of the flexible display directly affects the quality of the flexible display, so it is necessary to make an evaluation on the bending performance of the flexible screen, that is, detect the bending performance of the flexible screen after conducting an extrusion bending test to the flexible screen.
A drum-type bending device is always used in traditional methods and devices for bending test of flexible screen to mechanically bend the flexible screen. Specifically, a number of drums of a same curvature or different curvatures can be used to transmit the flexible screen to bend the flexible screen. If only one drum is used to transmit the flexible screen, a relative unit is required to press the flexible screen to bend the flexible screen; and if a plurality of drums are used to transmit the flexible screen, a drawing device is required to draw the flexible screen so that the flexible screen can be normally transmitted on the plurality of drums. Using a drum or a plurality of drums to transmit and bend the flexible screen has disadvantages of complexity of operation and high-cost of testing.